2-十三烷酮诱导的棉铃虫HaTrf基因调控细胞凋亡的分子机制

Transferrin is multifunctional gene in insects. We found RNAi HaTrf gene can significantly inhibited the insect growth and increased the susceptibility of larvae to 2-tridecanone. RNAi HaTrf also can accelerate the cell apoptosis induced by 2-tridecanone. In order to illustrate the mechanism of HaTrf gene mediated the cell apoptosis, this project plan to clone the promoter sequence of HaTrf, and then find the transcription factors which were associated with the cell apoptosis. In order to known the cell signaling pathway of HaTrf mediated the cell apoptosis, RNAi method and overexpression experiment will be used to detect the function of these transcription factors. This study can improve our knowledge about the interaction of insect pest and host plants, and contributes considerable gene resources to researchers interested in pest control.

昆虫转铁蛋白基因被认为是一种多功能基因。我们已发现2-十三烷酮能够诱导棉铃虫转铁蛋白基因的表达，干扰该基因的表达能够抑制棉铃虫的生长发育，同时降低棉铃虫对植物次生性物质2-十三烷酮的耐受性，在棉铃虫脂肪体细胞中干扰转铁蛋白基因表达加速了2-十三烷酮诱导的细胞凋亡。为了阐明2-十三烷酮诱导的棉铃虫转铁蛋白基因调控细胞凋亡的分子机制，本课题通过克隆棉铃虫转铁蛋白基因的启动子，研究2-十三烷酮诱导该基因的表达调控机制，确定出该基因启动子序列上可能参与2-十三烷酮诱导细胞凋亡有关的转录因子结合位点，进一步在棉铃虫脂肪体细胞中RNAi干扰及过量表达与细胞凋亡相关的转录因子，明确棉铃虫转铁蛋白基因加速2-十三烷酮诱导的细胞凋亡受什么细胞信号通路的调控。该研究对于阐明植物的抗虫性原理以及进一步利用功能基因控制害虫具有重要意义。

2-十三烷酮作为一种广泛存在于茄科植物的植物次生性物质，能够诱导棉铃虫转铁蛋白基因HaTrf的过量表达，同时我们发现2-十三烷酮处理后棉铃虫血淋巴中的铁离子和H2O2的浓度也出现了显著的升高，并运用RNAi干扰棉铃虫转铁蛋白基因的表达发现能够加速2-十三烷酮诱导的细胞凋亡现象，进一步通过对棉铃虫转铁蛋白基因启动子转录活性的分析，发现棉铃虫转铁蛋白基因介导的细胞凋亡现象受转录因子Cnc调控，推测HaTrf基因加速2-十三烷酮诱导的细胞凋亡是通过抗氧化信号通路Cnc调控。本研究为进一步研究转铁蛋白在昆虫与植物互作过程中的功能研究奠定了基础。